[A phase 2 study of recombinant interleukin 2 (S-6820) for head and neck cancer]

To evaluate the clinical efficacy and safety of a recombinant interleukin-2 (S-6820) therapy for head and neck cancer, a phase 2 study was conducted in a cooperative endeavor that has involved 23 institutions throughout Japan. Of the 81 patients in this study, 46 were eligible for an evaluation of the efficacy of this therapy. Two patients achieved a complete response (CR), and 4 patients achieved a partial response (PR). The overall efficacy rate was 13.0% (6/46), and good responses were obtained following a local injection either intratumorally or about the tumor. In contrast, a good result was not obtained from systemic administrations. WBC and lymphocyte counts in the peripheral blood increased and NK activity and LAK cells were seen to develop after treatment. Side effects were observed in 70.9% of 55 evaluable patients. These effects included fever (61.8%) or general fatigue (14.5%). In the laboratory findings, abnormalities such as eosinophilia were noted in 65.5% of patients.